HEATHER FACING CHILD CUSTODY CHALLENGE

HEATHER LOCKLEAR’s blowing off her family’s demand to check into rehab following her drugs/alcohol overdose debacle, and now she’s facing potentially worse trouble – ex-hubby RICHIE SAMBORA’s warned that if she doesn’t seek help he’ll petition the court to end their joint custody of 14-year-old daughter Ava and give him the child permanently.

Sources say the Bon Jovi rocker, clean and sober after completing his own rehab last June, keeps telling pals he literally fears for Heather’s life!